I bought it a few weeks ago on the forum here. While its' reach is staggering and I thought I wanted reach....once I had it available I didn't know what to do with it. I don't really do much nature photography and while it would probably be great at taking photos of the moon, I'm not sure how many times I'll actually use it. Here's an example of what 500mm will get you. mosaic26930330ec138758c2e72b75f13ca06c0466ca21 by Lukinosity (buried with work), on Flickr
The top shot is out my back window into my neighbors driveway taken with a 50mm lens, the one below is the 500mm......ahhhhh, the power of ten.

It has a few minor issues. There was a sticker on it that I peeled off and it left a bit of residue. If I were keeping it, I'd go out and buy something to take that off. Also, when I first used it and was turning the focus ring, there is a collar with a distance scale on it that came undone. It looked like there was some fresh adhesive underneath since it was still quite tacky. P9191313 by Lukinosity (buried with work), on Flickr
Possibly a "repair" that didn't quite take. Regardless, it still functions as it should.....except that you can't use the distance scale (which might be off anyways with the adapter in place).

It also had a skylight filter mounted to its' underside that I didn't know about...P9191314 by Lukinosity (buried with work), on Flickr
Front and rear caps as well. The Fotodiox Pentax to m43 adapter is in excellent condition.

It's certainly fun to play with and in the quality per dollar category for the focal length, it's hard to beat. It's just not my bag. Maybe it will be yours.